240 General: New (to me) 1980 Volvo 244

[Laird Scooby]

For some stupid reason, it won't let me post what i'm trying to but more or less agree except i think the value would be lower.

He's amended the window ECU listing on advice from someone by the way!

[Othen]

Originally Posted by Laird Scooby

That looks a useful bit of kit for less than an Ayrton Alan - have you got a link please?

I've got an old AVO branded digital automotive multimeter that was originally about £400 when new from RS plus the genuine leather case (another £80~) that i sometimes use but that needs connections to be made.

Fine for idle speed adjustments when there's no OE tacho in the car and similar but for a quick check or on something that doesn't have an electrical impulse to measure, it's a chocolate teapot.

No, just a barge............

The hand-held digital tachometer arrived in the mail today. For a tenner it is a pretty impressive little instrument, but not entirely without its issues.

After quite a bit of fiddling I managed to attach a piece of the reflective but not very sticky tape to the crank pulley (the PAS one), I had to use some gorilla glue, which worked okay after a bit of trial and error. This is not a very good photo, but perhaps you can see the little square of tape between the two belt runs:



The main issue with the instrument itself is the instructions: a very small leaflet that is translated straight from Chinese, probably via Google I should think. After a bit of playing around, and some practice aligning the sensor with the little bit of tape inside a very confined space with 3 fast belts rotating I got it to work quite well (not much health and safety in this household). I got the engine warmed and ticking over at a steady indicated 1000 RPM, the reading from the instrument was:



Well, 911 RPM is close enough to 900 RPM for government work, so I conclude the tick-over is set properly and the rev counter is reading fast by about 10% - much as I thought.

Stay safe.

Alan

[Laird Scooby]

All good stuff Alan - i wonder if a bit of Tipp-Ex on the pulley would work as well, now you've mastered the basic operation of the gadget?

[Stephen Edwin]

Following mathematical norms, round the result,

Or by slide rule principles.

2 x 2 = 3.9 call it 4.
RPM = 911 call it 900 ...

I hope that helps.





*****


Re China. If "people" want to stop The World being taken over by China, then, stop buying from China.

Think about it ....

More than difficult. So much Western branded products are made in People's Republic. And so I have bought lots of China products
and mea culpa but I am reviewing the situation.




.

[Othen]

I calibrated the digital thermometer against a fluorescent tube (at 50 Hz) and have found it to be really accurate:



... the result is not only as expected, but repeatable within 0.1%.

I think the instrument is quite remarkable for a tenner.

Stay safe.

[Stephen Edwin]

.... is that centigrade or farenheit ..... or Typometer ?????



Comrade Stephen Edwin ....

[Othen]

Originally Posted by Stephen Edwin

.... is that centigrade or farenheit ..... or Typometer ?????



Comrade Stephen Edwin ....

Comrade,

In revolutions per minute (RPM).

50 Hz x 2 maxima per cycle x 60 seconds = 6000 RPM

Is that what you meant (or maybe I missed something)?

[Stephen Edwin]

Dear Othen,

Thermometer. Or tachometer is that what you meant ... to say ... or perhaps typometer ?

We all do it. That one I just ... I did notice.

Comrade Stephen Edwin

[Laird Scooby]

Originally Posted by Othen

I calibrated the digital thermometer against a fluorescent tube (at 50 Hz) and have found it to be really accurate:



... the result is not only as expected, but repeatable within 0.1%.

I think the instrument is quite remarkable for a tenner.

Stay safe.

Originally Posted by Othen

Comrade,

In revolutions per minute (RPM).

50 Hz x 2 maxima per cycle x 60 seconds = 6000 RPM

Is that what you meant (or maybe I missed something)?

He has a point Alan - look at the first line of your post! I've made it bold and underlined.

That error works out at 0.05% maximum, certainly within tolerances and could even be down to mains frequency fluctuation which can be +/-1.5% anyway............

[Othen]

Originally Posted by Stephen Edwin

Dear Othen,

Thermometer. Or tachometer is that what you meant ... to say ... or perhaps typometer ?

We all do it. That one I just ... I did notice.

Comrade Stephen Edwin

Ah, silly me. Either fat fingers or dementia.